I flashed yesterday my 2002 SVT with the SCT tune, everything fine, but this morning during a traffic jam my iddle became weak, engine almost die. then the check engine light lited on, when got home scanned the ECU with the SCT and got this error code: PO171 (System too lean).

I flashed yesterday my 2002 SVT with the SCT tune, everything fine, but this morning during a traffic jam my iddle became weak, engine almost die. then the check engine light lited on, when got home scanned the ECU with the SCT and got this error code: PO171 (System too lean).

any ideas what would be causing the code?

i'd recommend you use a good gas cleaner everytime you fill up. i see that you are in GDL and I'm pretty the gas there sucks too. my dad used to always fill up and add a gas cleaner anytime we were in Mexico for a good amount of time.

Which device is being used to flash the vehicle? Are you using the preloaded tune files on that device or is it a custom tune file from an SCT dealer?

its an SF3 3015, I downloaded Strategy Tune, but the dealer told me that it has been custom tuned.

by the way, one more question, yesterday I got into program mode and set Idle at 1050, my concern is that after I done this the device prompted me to continue program or to cancel, I thoght that if I chose cancel wont save the changes, then I chose program and the device started to download the program again, about 15 minutes to complete. I think it doesn't hurt the car, BUT did I burnt one of the 5 atempts to donwload before if gets blocked permanently, or it only hapends when programing different vehicles (VIN)???

its an SF3 3015, I downloaded Strategy Tune, but the dealer told me that it has been custom tuned.

by the way, one more question, yesterday I got into program mode and set Idle at 1050, my concern is that after I done this the device prompted me to continue program or to cancel, I thoght that if I chose cancel wont save the changes, then I chose program and the device started to download the program again, about 15 minutes to complete. I think it doesn't hurt the car, BUT did I burnt one of the 5 atempts to donwload before if gets blocked permanently, or it only hapends when programing different vehicles (VIN)???

ive seen this a few times with tunes that my buddys have done and it means that you can change the tune 5 times with the current vehical's vin.before you have to reset the ecu back to factory tune. look for an aftermarket chip with an interior computer to save your tunes. your ecu will reconize these tunes that you save and wont count against your tunig changes!! (these are usually fairly expensive.)

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